Rating scales institutionalise a network of logical errors and conceptual problems in research practices: A rigorous analysis showing ways to tackle psychology's crises

This article explores in-depth the metatheoretical and methodological foundations on which rating scales-by their very conception, design and application-are built and traces their historical origins. It brings together independent lines of critique from different scholars and disciplines to map out the problem landscape, which centres on the failed distinction between psychology's study phenomena (e.g., experiences, everyday constructs) and the means of their exploration (e.g., terms, data, scientific constructs)-psychologists' cardinal error. Rigorous analyses reveal a dense network of 12 complexes of problematic concepts, misconceived assumptions and fallacies that support each other, making it difficult to be identified and recognised by those (unwittingly) relying on them (e.g., various forms of reductionism, logical errors of operationalism, constructification, naïve use of language, quantificationism, statisticism, result-based data generation, misconceived nomotheticism). Through the popularity of rating scales for efficient quantitative data generation, uncritically interpreted as psychological measurement, these problems have become institutionalised in a wide range of research practices and perpetuate psychology's crises (e.g., replication, confidence, validation, generalizability). The article provides an in-depth understanding that is needed to get to the root of these problems, which preclude not just measurement but also the scientific exploration of psychology's study phenomena and thus its development as a science. From each of the 12 problem complexes; specific theoretical concepts, methodologies and methods are derived as well as key directions of development. The analyses-based on three central axioms for transdisciplinary research on individuals, (1) complexity, (2) complementarity and (3) anthropogenicity-highlight that psychologists must (further) develop an explicit metatheory and unambiguous terminology as well as concepts and theories that conceive individuals as living beings, open self-organising systems with complementary phenomena and dynamic interrelations across their multi-layered systemic contexts-thus, theories not simply of elemental properties and structures but of processes, relations, dynamicity, subjectivity, emergence, catalysis and transformation. Philosophical and theoretical foundations of approaches suited for exploring these phenomena must be developed together with methods of data generation and methods of data analysis that are appropriately adapted to the peculiarities of psychologists' study phenomena (e.g., intra-individual variation, momentariness, contextuality). Psychology can profit greatly from its unique position at the intersection of many other disciplines and can learn from their advancements to develop research practices that are suited to tackle its crises holistically.

Problematic research practices in psychology: Misconceptions about data collection entail serious fallacies in data analysis

Given persistent problems (e.g., replicability), psychological research is increasingly scrutinised. Arocha (2021) critically analyses epistemological problems of positivism and the common population-level statistics, which follow Galtonian instead of Wundtian nomothetic methodologies and therefore cannot explore individual-level structures and processes. Like most critics, however, he focuses on only data analyses. But the challenges of psychological data generation are still hardly explored—especially the necessity to distinguish the study phenomena from the means to explore them (e.g., concepts, terms, methods). Widespread fallacies and insufficient consideration of the epistemological, theoretical, and methodological foundations of data generation—institutionalised in psychological jargon and the popular rating scale methods—entail serious problems in data analysis that are still largely overlooked, even in most proposals for improvements.

Three methodological core issues of comparative personality research

Comparative personality research in human and nonhuman species advances many areas of empirical and theoretical research. The methodological foundations underlying these attempts to explain personality, however, remain an unpopular and often ignored topic. The target paper and this rejoinder explore three methodological core issues in the philosophy of science for comparative personality research: Conceptualising personality variation, identifying domains of variation and measuring variation. Clear distinctions among these issues may help to avoid misunderstandings among different disciplines concerned with personality. Copyright © 2008 John Wiley & Sons, Ltd.

Comparative personality research: methodological approaches

In the broadest sense, personality refers to stable inter‐individual variability in behavioural organisation within a particular population. Researching personality in human as well as nonhuman species provides unique possibilities for comparisons across species with different phylogenies, ecologies and social systems. It also allows insights into mechanisms and processes of the evolution of population differences within and between species. The enormous diversity across species entails particular challenges to methodology. This paper explores theoretical approaches and analytical methods of deriving dimensions of inter‐individual variability on different population levels from a personality trait perspective. The existing diversity suggests that some populations, especially some species, may exhibit different or even unique trait domains. Therefore, a methodology is needed that identifies ecologically valid and comprehensive representations of the personality variation within each population. I taxonomise and compare current approaches in their suitability for this task. I propose a new bottom–up approach—the behavioural repertoire approach—that is tailored to the specific methodological requirements of comparative personality research. Initial empirical results in nonhuman primates emphasise the viability of this approach and highlight interesting implications for human personality research. Copyright © 2008 John Wiley & Sons, Ltd.

Taxonomic models of individual differences: a guide to transdisciplinary approaches

Models and constructs of individual differences are numerous and diverse. But detecting commonalities, differences and interrelations is hindered by the common abstract terms (e.g. 'personality', 'temperament', 'traits') that do not reveal the particular phenomena denoted. This article applies a transdisciplinary paradigm for research on individuals that builds on complexity theory and epistemological complementarity. Its philosophical, metatheoretical and methodological frameworks provide concepts to differentiate various kinds of phenomena (e.g. physiology, behaviour, psyche, language). They are used to scrutinize the field's basic concepts and to elaborate methodological foundations for taxonomizing individual variations in humans and other species. This guide to developing comprehensive and representative models explores the decisions taxonomists must make about which individual variations to include, which to retain and how to model them. Selection and reduction approaches from various disciplines are classified by their underlying rationales, pinpointing possibilities and limitations. Analyses highlight that individuals' complexity cannot be captured by one universal model. Instead, multiple models phenotypically taxonomizing different kinds of variability in different kinds of phenomena are needed to explore their causal and functional interrelations and ontogenetic development that are then modelled in integrative and explanatory taxonomies. This research agenda requires the expertise of many disciplines and is inherently transdisciplinary.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.

Diversity in action: exchange of perspectives and reflections on taxonomies of individual differences

Throughout the last 2500 years, the classification of individual differences in healthy people and their extreme expressions in mental disorders has remained one of the most difficult challenges in science that affects our ability to explore individuals' functioning, underlying psychobiological processes and pathways of development. To facilitate analyses of the principles required for studying individual differences, this theme issue brought together prominent scholars from diverse backgrounds of which many bring unique combinations of cross-disciplinary experiences and perspectives that help establish connections and promote exchange across disciplines. This final paper presents brief commentaries of some of our authors and further scholars exchanging perspectives and reflecting on the contributions of this theme issue.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.

Quantitative Data From Rating Scales: An Epistemological and Methodological Enquiry

Rating scales are popular methods for generating quantitative data directly by persons rather than automated technologies. But scholars increasingly challenge their foundations. This article contributes epistemological and methodological analyses of the processes involved in person-generated quantification. They are crucial for measurement because data analyses can reveal information about study phenomena only if relevant properties were encoded systematically in the data. The Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) is applied to explore psychological and social-science concepts of measurement and quantification, including representational measurement theory, psychometric theories and their precursors in psychophysics. These are compared to theories from metrology specifying object-dependence of measurement processes and subject-independence of outcomes as key criteria, which allow tracing data to the instances measured and the ways they were quantified. Separate histories notwithstanding, the article's basic premise is that general principles of scientific measurement and quantification should apply to all sciences. It elaborates principles by which these metrological criteria can be implemented also in psychology and social sciences, while considering their research objects' peculiarities. Application of these principles is illustrated by quantifications of individual-specific behaviors ('personality'). The demands rating methods impose on data-generating persons are deconstructed and compared with the demands involved in other quantitative methods (e.g., ethological observations). These analyses highlight problematic requirements for raters. Rating methods sufficiently specify neither the empirical study phenomena nor the symbolic systems used as data nor rules of assignment between them. Instead, pronounced individual differences in raters' interpretation and use of items and scales indicate considerable subjectivity in data generation. Together with recoding scale categories into numbers, this introduces a twofold break in the traceability of rating data, compromising interpretability of findings. These insights question common reliability and validity concepts for ratings and provide novel explanations for replicability problems. Specifically, rating methods standardize only data formats but not the actual data generation. Measurement requires data generation processes to be adapted to the study phenomena's properties and the measurement-executing persons' abilities and interpretations, rather than to numerical outcome formats facilitating statistical analyses. Researchers must finally investigate how people actually generate ratings to specify the representational systems underlying rating data.

Taxonomies of psychological individual differences: biological perspectives on millennia-long challenges

This Editorial highlights a unique focus of this theme issue on the biological perspectives in deriving psychological taxonomies coming from neurochemistry, neuroanatomy, neurophysiology, genetics, psychiatry, developmental and comparative psychology-as contrasted to more common discussions of socio-cultural concepts (personality) and methods (lexical approach). It points out the importance of the distinction between temperament and personality for studies in human and animal differential psychophysiology, psychiatry and psycho-pharmacology, sport and animal practices during the past century. It also highlights the inability of common statistical methods to handle nonlinear, feedback, contingent, dynamical and multi-level relationships between psychophysiological systems of consistent psychological traits discussed in this theme issue.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.

Interpreting "Personality" Taxonomies: Why Previous Models Cannot Capture Individual-Specific Experiencing, Behaviour, Functioning and Development. Major Taxonomic Tasks Still Lay Ahead

As science seeks to make generalisations, a science of individual peculiarities encounters intricate challenges. This article explores these challenges by applying the Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) and by exploring taxonomic "personality" research as an example. Analyses of researchers' interpretations of the taxonomic "personality" models, constructs and data that have been generated in the field reveal widespread erroneous assumptions about the abilities of previous methodologies to appropriately represent individual-specificity in the targeted phenomena. These assumptions, rooted in everyday thinking, fail to consider that individual-specificity and others' minds cannot be directly perceived, that abstract descriptions cannot serve as causal explanations, that between-individual structures cannot be isomorphic to within-individual structures, and that knowledge of compositional structures cannot explain the process structures of their functioning and development. These erroneous assumptions and serious methodological deficiencies in widely used standardised questionnaires have effectively prevented psychologists from establishing taxonomies that can comprehensively model individual-specificity in most of the kinds of phenomena explored as "personality", especially in experiencing and behaviour and in individuals' functioning and development. Contrary to previous assumptions, it is not universal models but rather different kinds of taxonomic models that are required for each of the different kinds of phenomena, variations and structures that are commonly conceived of as "personality". Consequently, to comprehensively explore individual-specificity, researchers have to apply a portfolio of complementary methodologies and develop different kinds of taxonomies, most of which have yet to be developed. Closing, the article derives some meta-desiderata for future research on individuals' "personality".

Developing "Personality" Taxonomies: Metatheoretical and Methodological Rationales Underlying Selection Approaches, Methods of Data Generation and Reduction Principles

Taxonomic "personality" models are widely used in research and applied fields. This article applies the Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) to scrutinise the three methodological steps that are required for developing comprehensive "personality" taxonomies: 1) the approaches used to select the phenomena and events to be studied, 2) the methods used to generate data about the selected phenomena and events and 3) the reduction principles used to extract the "most important" individual-specific variations for constructing "personality" taxonomies. Analyses of some currently popular taxonomies reveal frequent mismatches between the researchers' explicit and implicit metatheories about "personality" and the abilities of previous methodologies to capture the particular kinds of phenomena toward which they are targeted. Serious deficiencies that preclude scientific quantifications are identified in standardised questionnaires, psychology's established standard method of investigation. These mismatches and deficiencies derive from the lack of an explicit formulation and critical reflection on the philosophical and metatheoretical assumptions being made by scientists and from the established practice of radically matching the methodological tools to researchers' preconceived ideas and to pre-existing statistical theories rather than to the particular phenomena and individuals under study. These findings raise serious doubts about the ability of previous taxonomies to appropriately and comprehensively reflect the phenomena towards which they are targeted and the structures of individual-specificity occurring in them. The article elaborates and illustrates with empirical examples methodological principles that allow researchers to appropriately meet the metatheoretical requirements and that are suitable for comprehensively exploring individuals' "personality".

Conceiving "personality": Psychologist's challenges and basic fundamentals of the Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals

Scientists exploring individuals, as such scientists are individuals themselves and thus not independent from their objects of research, encounter profound challenges; in particular, high risks for anthropo-, ethno- and ego-centric biases and various fallacies in reasoning. The Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) aims to tackle these challenges by exploring and making explicit the philosophical presuppositions that are being made and the metatheories and methodologies that are used in the field. This article introduces basic fundamentals of the TPS-Paradigm including the epistemological principle of complementarity and metatheoretical concepts for exploring individuals as living organisms. Centrally, the TPS-Paradigm considers three metatheoretical properties (spatial location in relation to individuals' bodies, temporal extension, and physicality versus "non-physicality") that can be conceived in different forms for various kinds of phenomena explored in individuals (morphology, physiology, behaviour, the psyche, semiotic representations, artificially modified outer appearances and contexts). These properties, as they determine the phenomena's accessibility in everyday life and research, are used to elaborate philosophy-of-science foundations and to derive general methodological implications for the elementary problem of phenomenon-methodology matching and for scientific quantification of the various kinds of phenomena studied. On the basis of these foundations, the article explores the metatheories and methodologies that are used or needed to empirically study each given kind of phenomenon in individuals in general. Building on these general implications, the article derives special implications for exploring individuals' "personality", which the TPS-Paradigm conceives of as individual-specificity in all of the various kinds of phenomena studied in individuals.

Personality psychology: lexical approaches, assessment methods, and trait concepts reveal only half of the story--why it is time for a paradigm shift

This article develops a comprehensive philosophy-of-science for personality psychology that goes far beyond the scope of the lexical approaches, assessment methods, and trait concepts that currently prevail. One of the field's most important guiding scientific assumptions, the lexical hypothesis, is analysed from meta-theoretical viewpoints to reveal that it explicitly describes two sets of phenomena that must be clearly differentiated: 1) lexical repertoires and the representations that they encode and 2) the kinds of phenomena that are represented. Thus far, personality psychologists largely explored only the former, but have seriously neglected studying the latter. Meta-theoretical analyses of these different kinds of phenomena and their distinct natures, commonalities, differences, and interrelations reveal that personality psychology's focus on lexical approaches, assessment methods, and trait concepts entails a) erroneous meta-theoretical assumptions about what the phenomena being studied actually are, and thus how they can be analysed and interpreted, b) that contemporary personality psychology is largely based on everyday psychological knowledge, and c) a fundamental circularity in the scientific explanations used in trait psychology. These findings seriously challenge the widespread assumptions about the causal and universal status of the phenomena described by prominent personality models. The current state of knowledge about the lexical hypothesis is reviewed, and implications for personality psychology are discussed. Ten desiderata for future research are outlined to overcome the current paradigmatic fixations that are substantially hampering intellectual innovation and progress in the field.

How the great apes (Pan troglodytes, Pongo pygmaeus, Pan paniscus, Gorilla gorilla) perform on the reversed reward contingency task II: transfer to new quantities, long-term retention, and the impact of quantity ratios

We tested 6 chimpanzees (Pan troglodytes), 3 orangutans (Pongo pygmaeus), 4 bonobos (Pan paniscus), and 2 gorillas (Gorilla gorilla) in the reversed reward contingency task. Individuals were presented with pairs of quantities ranging between 0 and 6 food items. Prior to testing, some experienced apes had solved this task using 2 quantities while others were totally naïve. Experienced apes transferred their ability to multiple-novel pairs after 6 to 19 months had elapsed since their initial testing. Two out of 6 naïve apes (1 chimpanzee, 1 bonobo) solved the task--a proportion comparable to that of a previous study using 2 pairs of quantities. Their acquisition speed was also comparable to the successful subjects from that study. The ratio between quantities explained a large portion of the variance but affected naïve and experienced individuals differently. For smaller ratios, naïve individuals were well below 50% correct and experienced ones were well above 50%, yet both groups tended to converge toward 50% for larger ratios. Thus, some apes require no procedural modifications to overcome their strong bias for selecting the larger of 2 quantities.

How the great apes (Pan troglodytes, Pongo pygmaeus, Pan paniscus, and Gorilla gorilla) perform on the reversed contingency task: The effects of food quantity and food visibility

S. T. Boysen and G. G. Berntson (1995) found that chimpanzees performed poorly on a reversed contingency task in which they had to point to the smaller of 2 food quantities to acquire the larger quantity. The authors compared the performance of 4 great ape species (Pan troglodytes, Pongo pygmaeus, Pan paniscus, and Gorilla gorilla) on the reversed contingency task while manipulating food quantity (0-4 or 1-4) and food visibility (visible pairs or covered pairs). Results showed no systematic species differences but large individual differences. Some individuals of each species were able to solve the reversed contingency task. Both quantity and visibility of the food items had a significant effect on performance. Subjects performed better when the disparity between quantities was smaller and the quantities were not directly visible.

Prospective study of nosocomial fungal meningitis in children--report of 10 cases

Within an 8-year period, 10 cases of fungal nosocomial meningitis in children 0-13 y old were prospectively identified, 3 caused by yeasts other than Candida spp. (Rhodotorula rubra, Aureobasidium mansoni, Clavispora lusitaniae) and 7 by Candida albicans. Seven patients survived. whereas 3 neonates with fungal meningitis (all due to C. albicans) died. Risk factors for fungal nosocomial meningitis included cancer (2 children), previous neurosurgery (2 children), cranial trauma (1 case) and prematurity with low birthweight (5 cases). All patients except 1 had received broad-spectrum antibiotics before onset of meningitis. In addition to yeasts, bacteria were isolated from CSF of 4 children. One child had additional fungaemia. Univariate analysis was used to compare 10 cases of fungal to 91 cases of bacterial nosocomial meningitis. Except for concurrent bacteraemia, (60 vs 25.3%, P < 0.03), which was more frequently observed among fungal meningitis, there were no significant differences in risk factors, sequelae or outcome (mortality) between patients with fungal vs bacterial meningitis. A review of fungal meningitis reported within the last 20 y is included.

Ciprofloxacin in treatment of nosocomial meningitis in neonates and in infants: report of 12 cases and review

Twelve cases of neonatal and infant nosocomial meningitis treated with intravenous ciprofloxacin in doses of 10 to 60 mg/kg/day are described. Four neonates were 21 to 28 days old and eight infants were 2 to 6 months old. Six presented with Gram-negative meningitis: Escherichia coli (2), Salmonella enteritidis (1), Acinetobacter calcoaceticus (1), two with two organisms, and (H. influenzae plus Staphylococcus epidermidis, Acinetobacter spp. plus S. epidermidis), and six were attributable to Gram-positive cocci (four S. aureus and two Enterococcus faecalis). Ten cases were cured. In two cases, reversible hydrocephalus appeared that responded to intraventricular punctures. In seven children, no neurologic sequellae appeared after a 2- to 4-year follow-up. One neonate had relapse of meningitis 3 months later and was ultimately cured, but developed a sequellae of psychomotoric retardation. Follow-up varied from 27 months to 10 years. Current published case reports from Medline on quinolone use in meningitis in neonates and infants are reviewed.

Direct analysis and identification of Helicobacter and Campylobacter species by MALDI-TOF mass spectrometry

Campylobacter jejuni, Campylobacter fetus, and Campylobacter coli were compared with Helicobacter pylori and Helicobacter mustelae by direct analysis of individual cultured colonies in 50% methanol-water with a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS). H. pylori and Campylobacter species from blood agar culture produced unique, complex spectra with over 25 different ions in mass/charge (m/z) range from 2,000 to 62,000. A biomarker for H. pylori was centered around m/z 58,268, and H. mustelae was distinguished from H. pylori by its ions at m/z 49,608 and 57,231. Campylobacters could be distinguished from Helicobacters by their lack of ions around m/z 58,000 and 61,000 as well as distinguishing biomarkers of lower m/z: 10,074 and 25,478 for C. coli; m/z 10,285 and 12,901 for C. jejuni; m/z 10,726 and 11,289 for C. fetus. MALDI-TOF MS is a rapid and direct method for detection of these potentially pathogenic bacteria from culture.

Candida fungemia in neonates treated with fluconazole: report of forty cases, including eight with meningitis

PURPOSE OF THE STUDY

To assess efficacy and safety of fluconazole in neonates with Candida fungemia.

STUDY DESIGN

Multicenter prospective protocol of all fungemias appearing between January 1, 1993, and December 31, 1997, in four major university hospitals.

RESULTS

Forty neonates, 28 of them with very low birth weight (<1500 g; 30.5 median gestation week), with documented Candida albicans fungemia were treated with intravenous fluconazole in a daily dosage of 6 mg/kg once daily for 6 to 48 days. Thirty-four received fluconazole as monotherapy and 6 received it in combination with amphotericin B. Thirty-two (80%) were cured; 4 of them relapsed despite at least 14 days of therapy, but they were ultimately cured without sequelae. Eight other neonates died, 4 because of fungal infection and 4 because of prematurity or hemorrhage or lung failure, with fungemia (20% overall and 10% attributable mortality). Two neonates had elevated liver enzymes during fluconazole therapy and 2 others had elevated serum creatinine during fluconazole monotherapy. In none of them did these abnormalities necessitate discontinuation of antifungal therapy. In 8 neonates fungal meningitis developed as a complication of fungemia. All but 3 fungemias were C. albicans; 3 were Candida parapsilosis.

CONCLUSIONS

Fluconazole was safe and effective antifungal therapy even in complicated or Candida fungemia in neonates and in infants with very low birth weight.

Periovarian peritoneal adhesions in women with endometriosis. Structural patterns

OBJECTIVE

To draw attention to the structural features of adhesions associated with pelvic endometriosis since they are less well studied than endometriosis proper.

STUDY DESIGN

Sixty-two samples of periovarian adhesions were laparoscopically obtained from 24 infertile women 26-38 years of age and were prepared for detailed histologic analyses.

RESULTS

Macroscopically, the adhesions were either velamentous or cordlike and grossly were free of endometriosis. Most adhesions were attached to the connective tissue of the ovarian tunica albuginea; in two cases they were attached to the corpus luteum. Upon microscopic analysis, velamentous adhesions consisted of fibrous sheets of collagen connective tissue, with the surface lined with single-layered coelomic epithelium. The cord-like adhesions consisted of "hyalinized" fibrous tissue and were either avascular or vascularized. Irregular cystic or tubular structures that could be regarded as endometriosis were found in four patients. Hyaline cartilage within the tissue of the adhesion was an unexpected finding in one patient.

CONCLUSION

Microscopic analysis permitted grouping of the adhesions in the following way: (1) Connective tissue adhesions (23 patients) with the following subcategories: (A) fibrous, either avascular or encompassing degenerating blood vessels (6 patients); (B) vascularized, containing granulomatous tissue (12 patients); (C) vascularized with stromoglandular endometrioid cysts or tubules (4 patients); (D) rare types, such as that encompassing hyaline cartilage (1 patient). (2) Fibrin adhesions (1 patient). From the clinical point of view, the presence of endometrial tissue within adhesions raises the question of whether there is a need for removal, rather than just lysis, of adhesions to avoid persistent pain.

[Glycosaminoglycans in the peritoneal fluid of infertile women with endometriosis]

The authors examined the glycosaminoglycan level in the peritoneal fluid of 54 infertile women with or without endometriosis. The peritoneal fluid was collected during a routine laparoscopic examination. Glycosaminoglycans were assayed in complexes with Alcian blue. There was a higher concentration of glycosaminoglycans in peritoneal fluid during the follicular phase of women with endometriosis. The authors did not prove a statistically significant difference between women with and without endometriosis.

Transport of novel ovum surrogates in the human fallopian tube: a clinical study

Functional inadequacy of the fallopian tube cannot be adequately diagnosed by classical tubal patency tests. A new method using novel ova surrogates, microspheres transport test, is designed to diagnose dysfunctional tubal sterility. Biodegradable test microspheres with diameters matching that of the native ovum were used. According to the optimum procedure, the suspension of test microspheres was applied through the vaginal wall into the Douglas' space under local anesthesia, and the transported microspheres were collected in a modified cervical cap. The microspheres were readily identified in the sediment of cervical secretion by their fluorescence. The method was tested in 139 long-term infertility patients. Transport was observed in 100% of the control group, and positive correlation between the transport findings and the anticipated frequencies of dysfunctional tubal sterility cases in other groups was found. Optimum diameter of test microspheres was estimated at about 175 microns. The test appears to be useful for examination of functional disorders of the ovum transport in human practice.

[Treatment of liver rupture in an experiment]

The authors investigated in experiments on rabbits healing of liver incisions under various circumstances: spontaneous healing, liver incisions treated by suture by application of the tissue glue Tissucol, the collagenous haemostatic felt Collastypt combined with one stitch. Healing was followed up after several time intervals. From normal, i.e. the group of spontaneous healing, differed the groups treated by Tissucol and Collastypt where marked encapsulating fibrous tissue reactions round the necroses on the wound margins were found with numerous eosinophils as a transient phenomenon. The final result (with a maximum of cca two months) was adequate in all groups--as a rule a thin fibrous tissue scar with few remnants of atrophic hepatic trabeculae. In the treatment of small injuries it seems best to use the collagenous haemostatic Collastypt. In the treatment of sutures in rare instances a large number of leucocytes was found in the area of the necrosis and stitches, perhaps as result of contamination of the wound or sewing material.

[The role of compression plates and screws on changes in the internal conditions in long bones]

Morphological and biomechanical changes of the course of healing of cavities after screws in compression AO plates applied for 8 weeks and simple drilling revealed that in the long-term reduction of mechanical properties of these sites as a rule a major influence is played by transverse drillingholes of 3.4 mm and holes after 4.0 mm screws rather than by plates. The healing of cavities after simple drillingholes and after removal of screws is similar. In both instances a transversally oriented trabecular bony tissue is formed, i.e. transversally oriented to the original direction of osteones. This transverse orientation of trabecular bone matrix than causes poor distribution and spread of forces acting at these sites with a different vascular supply nutrition and biochemical changes. This reduces on a long-term basis biomechanical and other properties of these sites. Tranverse drillingholes and holes after screws are more important than plates in the subsequent reconstruction of osseous tissue after their removal. Therefore it is important when treating fractures using compression plates to keep in mind this adverse late effect of transverse cavities after screws and use them as little as possible.